Bale accumulators are well known agricultural machines used to accumulate a number of bales of crop material as the bales are pushed out of the bale casing of a rectangular baler. The bales may then be dumped in groups in a field for easier pickup, or may be transported to a remote location. As exemplified by U.S. Pat. No. 4,215,964, a typical bale accumulator of the prior art comprises a wheeled vehicle having a center, a right and a left table. The center table is fixed relative to the frame but the right and left tables may be unlatched so as to dump the bales thereon. A table is unlatched by an operator pulling a control rope. A caboose or fourth table may be attached to a bale accumulator such as the New Holland Inc Model 2010, the fourth table trailing the center table and being capable of dumping a bale located on the fourth table. A push bar is provided for moving bales ejected from the baler, and resting on the center table, onto the right or left table. By not actuating the push bar a succeeding bale ejected from the baler may push a bale on the center table onto the fourth table, if there is one.
With the prior art devices it is difficult to remember which tables have been dumped and which tables still hold bales. Furthermore, it is difficult for an operator to see all of the tables because the baler itself is large and blocks his view. To alleviate the problem it has been proposed that a system of mechanical flags be provided for signalling the operator which tables are occupied. However, such a system does not insure that the operator will choose to dump the bale or bales which should be dumped for most efficient use. For example, if all tables are full, the push arm is at the right of the center table, and the operator pulls the rope which causes the bale on the right table to be dumped, there is no way the right table can be loaded with another bale until after the left table has been dumped and then loaded with another bale.